AWS cloudformation intro

In

Pre-requisites

  • Install AWS CLI.
  • Configure it.
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    aws configure
  • Check it worked.
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    aws s3 ls

First contact with templates

  • Minimum example correction.
    • Initial script.
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      aws cloudformation create-stack \
        --template-body file:\\lamp-as.json \
        --stack-name lamp \
        --parameters \
        ParameterKey=KeyName,ParameterValue=mykey
        # won't work, needs more network elements information
        # such as VPCs, subNets info and DB access
    • Retrieve the lacking information from the CLI.
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      aws ec2 describe-vpcs
      aws ec2 describe-subnets
    • Complete template.
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      aws cloudformation create-stack \
        --template-body file:\\lamp-as.json \
        --stack-name lamp-as \
        --parameters \
        ParameterKey=KeyName,
        ParameterValue=mykey \
        ParameterKey=VpcId, \
        ParameterValue=vpc-1ffbc964 \
        ParameterKey=Subnets, \
        ParameterValue=\'subnet-0e170b31,subnet-52d6117c\' \
        ParameterKey=DBUser, \
        ParameterValue=myadmin \
        ParameterKey=DBPassword, \
        ParameterValue=mypass23
    • Once it is launched, verify.
      • Cloudformation is running.
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        aws cloudformation describe-stacks
      • EC2 instances are running.
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        aws ec2 describe-instances \
          --filters Name=instance-state-name,Values=running \
          --query 'Reservations[*].Instances[*]\
              .{Instance:InstanceId,PublicIPAddress:PublicIpAddress}'

Get help for filling up more AWS fields

  • Retrieve information about stacks. 
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    aws cloudformation describe-stacks
  • Define the EC2 instance type on template.
    • You may swap that default value for any of the other AllowedValues, or override it from the CLI.
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      "Parameters" : {
        "KeyName": {
          "Description" : "Name of an existing EC2 KeyPair to enable SSH access to the instance",
          "Type": "AWS::EC2::KeyPair::KeyName",
          "ConstraintDescription" : "must be the name of an existing EC2 KeyPair."
        },

        "InstanceType" : {
          "Description" : "WebServer EC2 instance type",
          "Type" : "String",
          "Default" : "t2.small",
    • Check Mappings section,to review available hardware architectures and AMI identifiers for each region.
      • Optional section, you can insert your own non-standard values organized into key\value pairs.
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        "Mappings" : {
          "AWSInstanceType2Arch" : {
            "t1.micro"    : { "Arch" : "HVM64"  },
            "t2.nano"     : { "Arch" : "HVM64"  },
            "t2.micro"    : { "Arch" : "HVM64"  },
      • The Resources section in this case defines your instance environment (public IP address is associated with the new Elastic IP address that will be allocated).
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        "Resources" : {
          # ...
          "InstanceSecurityGroup" : {
            "Type" : "AWS::EC2::SecurityGroup",
            "Properties" : {
              "GroupDescription" : "Enable SSH access via port 22",
                "SecurityGroupIngress" : [ {
                "IpProtocol" : "tcp",
                "FromPort" : "22",
                "ToPort" : "22",
                "CidrIp" : { "Ref" : "SSHLocation"}
              } ]
            }
          }
        },

Get help with external stacks

  • Quick Starts - pre-built infrastructure stacks that are provided here to help you create more complex cloud deployments by third-party companies to simplify the process of building their infrastructure in within the AWS platform.